Skeletal vs Plinth style turntables

Hi Henry, I was hoping you would come out of your recent shell. Once again, you've written nothing that comes remotely close to changing my mind about outboard arm pods. However, I do agree with you on some of the other issues... Where was it exactly that I was talking about "airborne feedback". That's your pet bugaboo; you raise the issue in order to beat it to death. I've never used the term.

The way I read Atma-sphere's post, I should think you would have to disagree with some of it. He is saying what I have always said. To wit, "To this end, the coupling between the bearing and the base of the arm must be as precise and tight as possible; IOW of a singe piece which will not respond to vibration, as if any differences can occur they will be interpreted by the pickup as coloration."

Take a look at an L07D some time. There is the epitome of what I and Atma are talking about in terms of "coupling".

All of this folderol aside, I have come to think of you as a friend and I would love to argue these silly issues with you over a Foster's, if and when I ever make it back to Oz.

You girls play nice in the sand box now.

Once again, you've written nothing that comes remotely close to changing my mind about outboard arm pods.

Dear Lew.....my mate...😍
It is not my desire to change your mind about anything...
I know better..😏
I simply use my ears and listen to actual examples BEFORE I blindly theorise..
Chances are I'll be back in the States before you make it to Oz..❓
If there's no Fosters there...a nice Chivas might have to do...👍

Halcro and Lewm - it's like those two old men on the muppets - always arguing - probably really the best of friends/enemies??? Funny thing is that both write about some of the best posts on this forum from my reading.
What Halcro says then explains why people like Mike Lavigne are using very expensive microscope stands in their systems.
That said don't RIAA filters etc cut out above 2-5 hz?
I guess I am gonna have to put theories into a design, and then tune using my ears.

Dgarretson
Ct0517 and RichardKrebs, have you considered filling the webbed aluminum casting of an SP-10 with a dense hard mixture of industrial epoxy and crushed granite(similar to Verdier) or brass powder? This might give the casting the properties of a massive plinth, while performing in conjunction with a rigid skeletal "plinthless" sub-frame.

@Dgarretson

Hi Dave - did not realize you picked up a SP10MKII. another TT ?
Filling the webbed aluminum casting sounds like a good idea. But when you say "plinthless" with my set up it is not the case. if i can backtrack.

I got to about Version 8
with my SP10 project (two + years ago?)

The plinth can be seen as the black base that the stainless steel columns and pod are bolted into.

It has not been touched in a long time.
I admit its looking kind of stale and I always meant to replace the current black base with a more aesthetic one.
This hobby is very much an exercise of Function over Form for me. The tonearm attached to the POD is a leading example of this.
If for some reason one "hears" a mismatch in resonances, the ET2 provides resonances tuning capability.
If I had continued with the SP10 I had thought of maybe dropping its black pants and have a look at how things can be cleaned up. I discussed with Richard Krebs, sending it to him long ago.

I have also though of maybe give the SP10 some balls ?

however.... as I am really enjoying not reporting to a boss (wife not included) I need to be selective with funds for the hobby as I have two 20 years olds grabbing cash at every opportunity. Its not a priority and the sp10 is in room 2.
All my vinyl listening is on La Platine in room one.

fwiw (sorry to digress Parottbee)
My turntable phase was a very slippery slope for me. It came at a time when I needed something to take my mind off other things.
I am very grateful for it and I learned much with my SP10MKII. I am happily a music lover these days, with no desire to tinker, although I don't mind talking shop on the forums and discussing past experiences. I did have at the height of my own personal madness - three tables, modded VPI TNT ( thread drive), SP10MKII and Nantais lenco table (which btw used to be his personal table), all next to one another like babies in a nursery. I had the same tonearm / cartridge going with two of them at a time, and it was alot of fun comparing to 15 IPS master tape dubs - very revealing.

Back to the thread theme if I can just say that discussing the type of plinth is only one aspect of this. The platter system is very important.
For example the Jean Nantais
here is what the platter looks like

I have a copper mat I can use with the technics.

The Verdier however again sets the mark - a solid aluminum platter designed to be used Naked.
With the magnetic levitation the natural action of magnets producing a braking action. So you have acceleration inertia and and braking due to the opposed pole magnets to deal with the records behavior. Add to this a solid aluminum rigidly attached pod, a different material brass spindle to interact separately from the platter. oh yeah also no bearing....... Just bloody brilliant. Continually amazed by the simplicity of it. In all my years at this hobby probably the best thing I have acquired right there with my SP11 (and my records)

Henry - Lewm seems to showing (again) what we in Canada refer to as - possible signs of cabin fever. I could be wrong . But if I am not mistaken there have been some bad snow storms in the US lately. :^)

God, these analog threads make the digital ones seem SO BORING....... no more coffee for me. :^(

Cheers